To be deemed affordable and thus qualify for state subsidy, new homes must be offered to tenants at a maximum of 80% of local market rents. To call this affordable betrays a staggering lack of awareness. In the real world, 80% is not much cheaper than the expensive rents set by the free market; it is not affordable to people on average incomes in expensive areas, let alone those on low incomes whom subsidised housing is supposed to prioritise.

So when government MPs pat themselves on the back about rates of affordable housebuilding, they're not actually talking about homes that are going to help Britain's neediest.

Labour's housing spokesman Emma Reynolds has now pledged to redefine affordability of housing to make it "relative to incomes and house prices". That a Labour government will throw out this ridiculous and corrosive item of newspeak is common sense and should barely merit acknowledgement. But the possibility of affordable being defined by house prices - subject to the same inflationary effects as rents if not more so - is as bonkers as the coalition's policy. It is hard to believe that any politician can credibly define affordability in relation to anything other than wages.

The response from the housing minister, Brandon Lewis, would be amusing if it weren't so enraging. He said redefinition of affordability could "undermine" the delivery of affordable housing. This is like saying that reclassifying horses as unicorns would be damaging to unicorns.

Ultimately language only goes so far, and any government that wants more homes to be affordable to people on low incomes must use public cash to build them. If we're to believe the buy-to-let industry, there's no better investment than property.